The main diseases and insect pests of Cymbidium

(1) fungal diseases.

Root rot: such as blight, white silk disease and so on. Due to fungal infection, orchid root disease, root skin rot and exfoliation, and then neck rot, leaf base rot, and finally died. The seedling infection was stunted and died.

Black rot: infected by fungi with symptoms similar to root rot.

Leaf diseases: such as anthracnose, round spot, leaf spot, leaf pollution, fly feces, rust, scorch blight and so on.

(2) bacterial diseases.

Brown spot: Brown patches on the leaves of orchids caused by bacterial infection.

Soft rot: soft rot of tender tissues such as pseudobulbs and rhizomes caused by bacterial infection. The leaves lose their luster and droop and die.

Brown rot: the leaf becomes brown after the macula is infected by bacteria. if it invades the growing point of the leaf, the upper part dries up and dies.

(3) virus diseases.

Due to the invasion of virus, the leaves appeared sunken stripe spot, ring spot, orchid plant dwarfism and distortion. The common Ballas disease also falls into this category.

(4) insect pests.

Shell insects: White dots scattered on the surface and back of the leaves, absorbing nutrients and making the leaves yellow. The eggs are wrapped in wax and attached to the leaves.

Red spider: the worm is very small and difficult to find, biting the back of the leaves and showing rust spots.

(5) diseases caused by other causes.

Lack of certain elements: such as nitrogen, phosphorus, iron, magnesium, molybdenum, sulfur and other elements, the color of leaves will become worse; lack of calcium, zinc, copper, magnesium, sodium and other elements, orchid plants will yellowing or necrosis.

Fertilizer damage: the application of immature organic fertilizer or excessive application of chemical fertilizer will decompose into harmful gases to poison the ink orchid, the leaves will appear black spots first, and wilt and die in serious cases.

Drug damage: improper release of drugs will also appear dark brown spots, serious necrosis.

The air and water sources are contaminated: it will infringe upon the ink orchid, causing it to grow badly and die. Common are gas, soot, oil fume and other harmful gases and acid rain. (Yan Xueliang)